I. Field of the Invention
The present invention relates to a tranverse beating mechanism for a grape harvesting machine. It also concerns the beater kinematics.
II. Description of the Prior Art
The grape harvesting machines of known type are provided with two series of beaters disposed on either side of the row of vines concerned. These beaters are imparted a transverse motion to transmit to the grapes a speed sufficient for tearing the clusters of grapes away from the vine. The main problem is, firstly to adjust the initial position of the beaters, then to determine the proper transverse oscillation frequency permitting to collect the maximum of intact grapes without submitting the vine to injuries, i.e., without plucking off the leaves and without breaking the shoots.
When the beaters are horizontal whips, the known mechanisms keep substantially constant the spacing between two opposite points during the whole motion of the beater members. It is obvious that such devices have the major drawback to comply only with one of the two preceding conditions, namely:
If the spacing between two opposite beater points is reduced, most of the grapes will be collected, but the vine will be injured; PA0 If the spacing between two opposite beater points is increased, the percentage of grapes collected will be insufficient; it would be then necessary to increase the beaters oscillation frequency, which would again result in injuring the vines. PA0 Asymmetrical motions can be imparted to opposite beaters; PA0 The spacing between two opposite beaters points can be varied during the machine operation, by means of an adequate mechanism.
Known improvements have been developed by the present applicant, namely:
However, all the grape harvesting machines of known type are provided with a bearing mechanism which necessitates a preliminary adjustment. This pre-adjustment is satisfactory only under the following conditions:
(A) All the vines of one row must be exactly in line. Otherwise, i.e., if some vines are shifted out of the row, or if some vine shoots extend more on one side of the row, then more on the other side, the percentage of harvested grapes is decreasing, while the leaves plucking off is increasing.
(B) The vine characteristics (foliage density, etc . . . ) must be constant all along the row. Otherwise, operation defects are appearing, specially at places where a vine plant is missing.
Quite obviously, both those conditions are never perfectly complied with on the whole vine field area, so that the grape harvesting is not entirely satisfactory.
It has been found quite remarkable that, when using a beating mechanism according to French Pat. No. 2,213,003, now U.S. Pat. No. 3,939,629, the beater driving eccentric located close to the vine row (and connected to the beating whips) is subject to a relatively small effort; most of the efforts are supported by the connecting rod within which the second eccentric is rotating. These main efforts result from the reactions to the accelerations which are imparted to the grape clusters by the beating whips, since the vines are not struck, but continuously moved and oscillated.